LoadError: Could not load the 'listen' gem (Rails 5)

Question

I\'ve got an API mode Rails 5 app that won\'t let me run rake routes or rails s. The error I get is:

$ rake routes
rake aborted!
Lo         


        

Answer 1

I'm posting this as an answer, but I don't like it.

I can "fix" the problem by putting gem 'listen', '~> 3.1.5' in the global Gemfile (and removing it from :development). Then all the errors go away and everything works, but that seems wrong.

Answer 2

I had the same problem, i fix it by running

rails c -e production

Answer 3

I used this: bundle install --without development

Error:

Could not load the 'listen' gem. Add gem 'listen' to the development group of your Gemfile (LoadError)

After this, use that code:

bundle config --delete without
bundle config --delete with

Finally

bundle install

Answer 4

If you are on rails 5 and you are using the default config/environments/development.rb file it will have this line of code in there.

config.file_watcher = ActiveSupport::EventedFileUpdateChecker

This requires the gem listen. This threw me for a bit as I was doing a rails 4 upgrades to a rails 5

edit: Forgot to mention that if you comment that line of code out it will not need the listen gem anymore.

Answer 5

I had the same issue. Thanks to @newdark answer I figured out the correct solution. Basically I wanted to deploy rails in production mode. But obviously forgot to set environment variable RAILS_ENV=production before running server.

So to recap, dependencies for production mode were installed while rails tried to start in development mode due to forgetting to set RAILS_ENV=production. If I went on to add gem listen to the production dependencies, I'd be running in development mode without being able to notice.

For me the solution was to do export RAILS_ENV=production before executing any rails commands and keep dependencies intact. Hope I managed to explain.

Answer 6

I'm having the same problem by running rails c.

By reading this other Stack Overflow post I did realize that it is normal that both bundle exec rake command or rails console are running in a default production environment.

I figured I will solve the issue either by:

1. adding export RAILS_ENV=production in ~/.bash_profile
2. explicitly writing the environment in which I want the command to execute like bundle exec rake a_rake:task RAILS_ENV=production rails console --env=production etc...